Mining methods using equipment suspended from roof-mounted rails

ABSTRACT

A method for mining in barren rocks or orebodies in order to bring about substantially horizontal drifts or upwardly inclined drifts having an inclination less than the angle of repose of the loosened material, and vertical mining of underground cavities, respectively and that said mining is carried out with a mining unit, which is movably suspended on rail means in the roof of said drifts or underground cavity, and that said loosened material is removed by a loading unit and a haulage carriage, which also are suspended on said rail means for moving thereon either individually or joined together.

United States Patent [191 Granskog et al.

[ 1 May 8,1973

[75] Inventors: Roland Granskog; Rolf Degerman,

both of Skelleftea, Sweden [73] Assignee: Linden-Alimali AF; "'slilleft'e'a,

Sweden [22] Filed: Sept. 14, 1970 [21] Appl. No.: 71,939

[52] U.S. Cl. ..299/l8, 173/22, 173/31, 214/1 MS [51] Int. Cl. ..E21c 35/20 [58] Field of Search ..173/22, 31, 32; 299/11,18, 33, 55,56, 6468; 214/1 MS; 104/89 [56] References Cited UNITED STATES PATENTS 1,992,129 2/1935 Parker ..299/64 3,219,199 11/1965 Lagerstrom ..2l4/1 MS 3,574,405 4/1971 Shimada et a1. ..299/64 2,176,885 10/1939 Cadwallader ..299/33 X 2,375,689 5/1945 Reeder ....299/18 X 1,570,386 1/1926 MacCarthy et a]. ....299/18 X 2,195,544 4/1940 Stahl ct a1 ..299/18 X FOREIGN PATENTS OR APPLICATIONS 132,159 1960 U.S.S.R. ..299/l8 Primary Examiner-Ernest R. Purser Attorney-Sommers 8L Young 57] ABSTRACT A method for mining in barren rocks or orebodies in order to bring about substantially horizontal drifts or upwardly inclined drifts having an inclination less than the angle of repose of the loosened material, and vertical mining of underground cavities, respectively and that said mining is carried out with a mining unit, which is movably suspended on rail means in the roof of said drifts or underground cavity, and that said loosened material is removed by a loading unit and a haulage carriage, which also are suspended on said rail means for moving thereon either individually or joined together.

15 Claims, 4 Drawing Figures MINING METHODS USING EQUIPMENT SUSPENDED FROM ROOF-MOUNTED RAILS BACKGROUND OF THE INVENTION The invention relates to a method for mining in barren rocks or orebodies in order to bring about horizontal drifts or upwardly inclined drifts having an inclination less than the angle of repose of the loosened material as well as vertical mining of underground cavities as in conventional shrinkage stoping and certain forms of overhand stoping.

The driving of drifts having an inclination less than the angle of repose of the loosened material, is different from vertical as well as inclined drift mining, in which the angle of repose of the inclined drift is greater than that of the loosened material. These mining operations are, at present, completely unmechanized, and the drifts are driven by means of handoperated hand drills with the loosened material being removed by means of scraping devices and vehicles which, because of the space they required, prevent an immediate resumption of operation the mining, thus leading to a low mining capacity with accompanying bad economy.

In known conventional shrinkage stopage only approximately 40 percent of the loosened ore and/or rock can be gathered during the phase of driving. The remaining lot must be left to provide a platform for the mining equipment and the miners, which thus involves a bad economical utilization, as the capital invested yields full economical return only at the final phase of tapping. If furthermore the hanging walls come down during the phase of tapping great ore losses are in most cases unavoidable and, in addition, conventional shrinkage stoping cannot be used for mining ores and/or rocks containing substances which make housing impossible.

In overhand stoping, in which method the platform for the drilling equipment and the miners is provided by filling with sand, through which sand tubes of metal are driven for tapping of the loosened ore and/or rock, the whole ore and/or rock quantity can certainly be directly tapped off after the mining, but the costs for the equipment and the sand necessary for the filling still remain.

The object of the present invention is to provide a method for mining in barren rocks or orebodies, which method eliminates the above mentioned disadvantages.

SUMMARY OF THE INVENTION The present method for mining in barren rocks or orebodies in order to bring about substantially horizontal drifts or upwardly inclined drifts having an inclination less than the angle of repose of the loosened material, and shrinkage stoping, respectively, is characterized in that the mining is carried out with a mining unit, which is movably suspended on rail means in the roof of said drifts and underground cavity. As material is loosened during the phase of driving of upwardly inclined drifts having an inclination less than the angle of repose of the loosened material, the loosened material is removed by a loading unit and a haulage carriage, which also are suspended on said rail means and movable thereon individually or joined to one another.

The removal of the loosened-material is preferably started at the center of said loosened material. The

loading unit comprises a frame, a loading pipe, a scraper and a scrape loader, and is preferably movable upwards along the rail means either by the mining unit or the haulage carriage. The latter can be moved by a drive unit incorporating a pneumatic or electric motor or an internal combustion engine.

BRIEF DESCRIPTION OF THE DRAWINGS The invention is further described below with reference to the attached. drawing in which FIG. 1 shows a vertical section through a drift inclined in proportion to the horizontal plane and a mining equipment for carrying out the method according to the invention, FIG. 2 shows a top view of FIG. 1, FIG. 3 shows a vertical section through an underground cavity, a haulage drift, a raise and a service drift and the mining equipment for carrying out the method according to the invention, and FIG. 4 shows a vertical section through a drift inclined in proportion to the horizontal plane and mining and material removal equipment for carrying out the method according to the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, rail means 1 are fastened in the roof 3 of drift 2. Said rail means 1 are preferably fastened by expansion bolts. The rail means preferably consist of standard units, which facilitate the handling and increase the carrying capacity of the same. The mining is carried out with a mining unit 4, which is suspended on the rail means. The communication with the mining unit 4 is kept up by means of an elevatorcage-similar travelling Waggon 5, and furthermore the mining unit 4 is preferably moved along the rail means 1 by a drive unit, which can be airdriven, the air being supplied to the drive through hoses from hose reels 6, which are arranged in a service room 16 while the hoses being arranged on rollers along the rail means 1. Air and water are supplied to the mining unit 4 through the rail means 1. Owing to the fact that loosened ore and/or rock 7 falls down a distance in the drift 2 and in that connection uncovers a more or less vertical face 8 close to the roof 3 of the drift 2,'it is possible by means of the mining unit 4, suspended on the rail means 1 fastened to the roof, to immediately resume the mining and thus not as before to wait until the ore and/or rock 7 has been removed.

The method according to the invention applied to shrinkage stoping (see FIG. 3) is started from a haulage drift 9, from which a raise 10 is driven up to a service drift 11, the work being carried out with a raise climber on rail means preferably consisting of standard units. From the haulage drift 9 there is then driven a number of tapping holes 12 up to a drift, driven above and parallel with the haulage drift 9 and constituting the lower part of the underground cavity 13. The driving of the drift parallel with the haulage drift 9 is carried out with conventional methods or as described above. The ore and/or rock loosened during the preparatory work is tapped off from the underground cavity 13 to the haulage drift 9 through the tapping holes 12.

After the preparatory work is finished the actual mining is started. At first the rail means 1 is lengthened so that the vertical direction of said rail means through bow-shaped connecting units 14 is changed into horizontal direction in the service drift 11. The mining unit 4, the travelling waggon 5, the hose reels 6, the hoses, the necessary rail means and other equipment are then transported to the service drift 11 where said mining unit 4 and travelling Waggon 5 are mounted on the horizontal part of said rail means 1.

The mining unit 4 is then driven down in the raise for preparation of the curve between the raise 9 and the roof of the underground cavity, whereupon the rail means are so lengthened that the vertical direction of the same through bow-shaped connecting units change into horizontal direction along the roof of the underground cavity 13. The lengthening and fastening of the rail means is carried out from a platform, arranged at the front part of the mining unit 4. Then, the horizontal mining of the roof of the underground cavity is started, the blasting being electrically controlled from the service drift 11. After the blasting operation the mining unit 4 is again driven down in underground cavity 13, whereupon the roof is scraped and necessary rail means 1 are mounted. The horizontal mining is repeated stepwise throughout the whole underground cavity 13.

At that end of the underground cavity 13 located remotest from the raise l0, fan-shaped vertical mining is started after the horizontal mining is finished.

After the vertical mining is finished, the drill holes are charged and the rail means I removed from the mining area, whereupon the blasting is carried out. The volume of ore and/or rock loosened at each blasting is determined by the actual blasting factors. By repeating this operation the initial position at the raise 10 will be reached. The work cycle is repeated in this way a number of times depending on the height of the raise 10, which height in turn depends on the strength of the walls of the underground cavity.

In the method according to the invention applied to upwardly inclined drifts having an inclination less than the angle of repose of the loosened material (see FIG. 4) the driving of the drifts is carried out by means of the mining unit 4, for example a drill unit, which is provided with one or more hydraulically and independently operated booms with feeders. A special platform is furthermore provided for scaling, charging, changing of drill steels etc.. The drill unit 4 and the feeders are driven by air, supplied through the rail means 1, and the drive units for the travelling Waggon are preferably of the same, well-known type used in the above mentioned raise climbers and are driven either by air or electricity, supplied through hoses and cables, or by an internal combustion engine. The oil for the hydraulic system is delivered by an air-driven pump unit.

The loosened material is then removed by a material removing device comprising a loading unit 17 and a haulage carriage 18 which, like the drill unit 4, are movable along the rail means 1 arranged in the roof of the drift 2. The loading unit comprises a frame 19, a loading pipe 20, a scraper 21 and a scrape loader 22. The loading unit 17 has no drive unit and is pulled up along the rail means 1 to the face 8 by means of the drill unit 4 or the haulage carriage 18. Two hydraulic jack legs are furthermore provided as a support during the mucking. Then the loosened material is removed by the haulage carriage 18.

The different parts of the equipment should balance each other so that loading and transport would take about the same time that would be necessary to get the next round ready.

The method is preferably carried out by only two men (one for drilling, one for loading and transport), which is considered to be of great advantage compared with methods practiced so far.

As soon as the drift 2 is accessible after a blast, lengthening of the rail means 1, scaling and drilling can be made at the same time that the mucking is carried out. The air of ventilation is supplied through the rail means 1.

The removal of the loosened material is preferably carried out as follows. First of all the pulleys 23 of the scrape loader 22 is fastened to the face 8, whereupon the scraping is started in the center line of the drift 2 at the same time as the drilling at the roof of the drift 2 can be started. It is important, that the scraping of the loosened material be started in the center of the drift as this will make it possible to start drilling a new cut as early as possible.

The scraping can be finished while the cut and the holes in the upper part of the face 8 are being drilled, after which the loader can start to prepare the chargmg.

The mining as well as loading and transport is completely mechanized and thus labor-saving.

The mining capacity is quite satisfactory as one, two or more drilling machines can be working simultaneously.

Although the invention is described with the mining unit (drill unit) and the material removal device suspended on one string of rail means it is clear that they also can be suspended on two or more strings of rail means, if that is considered necessary in view of the weight etc. of the device.

What we claim is:

l. A method for vertical mining of underground cavities wherein said mining is carried out with a drill unit which is movably suspended on rail means fastened to the roof of said underground cavity and extending along said roof into a raise, whereby said drill unit can be removed from the mining area during blasting operations and loosened material can be removed without hindrance during the drilling operations, the mining operations being started at that end of the underground cavity located remotest from the raise connected thereto and being carried out stepwise towards and up to said raise; a first roof area is drilled, the rail means fastened to the roof of the underground cavity are removed only from that portion of roof area which has been drilled, and the drilled roof area is then blasted away; thereafter a new roof area located nearer said raise is drilled, the rail means fastened to the new drilled roof area is removed, and the blasting thereof is carried out; this procedure is repeated until said raise is reached; and rail means are then fastened in the new roof formed and the process repeated until the height of the underground cavity equals that of the raise.

2. A method for mining in barren rocks or ore bodies comprising the step of driving a haulage drift, driving a raise upwards from said haulage drift, driving a parallel drift parallel with and above said haulage drift, and driving tapping holes for loosened material between said parallel drift and said haulage drift, whereafter rail means are secured to the roof of the parallel drift and mining equipment which includes a drill unit is movably suspended from said rail means, horizontal breaking is started from said mining equipment and continues stepwise by the installation of new rail means as the work progresses, the mining equipment being brought into safety between each blasting via said raise, whereupon, when the horizontal mining is finished, and a horizontally widened cavity is thereby obtained, vertical mining is started and carried out from said suspended equipment over the full area of the roof of said cavity to remove a layer of a certain thickness from said area, the mining equipment including the rail means is then withdrawn to the raise and the rail means are fastened in the new roof formed, and the vertical mining process is repeated for a next layer of the roof, the vertical mining being repeated a number of times determined by the height of said raise and the thickness of said layers.

3. A method according to claim 2 wherein, during the successive vertical mining, when a new set of rail means have been installed on the roof of the cavity, mining is started each time at a location as remote as possible from the raise and is carried out stepwise by drilling a first roof area, removing the rail means fastened to said first area, blasting said first area, thereafter drilling a new roof area located nearer said raise, removing the rail means fastened to said new area, blasting said new area, and so on until said raise is reached. 1

4. A method according to claim 3 wherein said stepwise mining is carried out in a fan-shaped pattern.

5. A method according to claim 2 wherein, during or after the forming of said raise, rail means are fastened in the wall of the raise, whereupon said rail means on the successive roofs of the parallel drift and said cavity are connected to said rail means on the wall of the raise in order to facilitate withdrawal of the mining equipment.

6. A method according to claim 5 wherein a service drift is arranged to end in the raise at a place remote from the cavity and further rail means are installed in the roof of said service drift and connected to the rail means of the raise whereby, during mining, blasting is remotely controlled from said service drift.

7. A method for driving, in barren rocks or ore bodies, substantially horizontal drifts or upwardly inclined drifts having an inclination less than the angle of repose of the loosened material, comprising the steps of removably securing rail means to the roof of said drift, movably suspending from said rail means a mining equipment which includes a drill unit, drilling and loading blast holes from said suspended mining equipment, moving the mining equipment to a safe position via the rail means, blasting, bringing the mining equipment forward again via the rail mean to the working area independently of the extent to which loosened material has been spread away from the blasting area along the drift, and repeating the drilling and loading steps while simultaneously removing the loosened material.

8. The method of claim 7 including the step of movably suspending a material removal device from said rail means, said step of rempvin' the loosened material being effected with the and o the suspended material removal device.

9. A method according to claim 8 wherein the loading of said removal device is started in the center of the loosened material.

l0. Apparatus for driving substantially horizontal drifts or upwardly inclined drifts in barren rocks or ore bodies with said drifts having an inclination less than the angle of repose of the material which is loosened during said driving, comprising rail means removably fastened to the roof of the drift, a mining equipment including a drill unit movably suspended from said roofmounted rail means, a loading unit, a haulage carriage, and means for movably suspending said loading unit and said haulage carriage from said rail means.

11. Apparatus according to claim 10, wherein the loading unit comprises a frame, a loading pipe, a scraper, and a scrape loader.

12. Apparatus according to claim 10, wherein the loading unit is movable upwards along the rail means either by a drill unit or the haulage carriage.

13. Apparatus according to claim 10, wherein the haulage carriage is movable by a pneumatic drive unit.

14. Apparatus according to claim 10, whereinthe haulage carriage is movable by an electric motor drive unit.

15. Apparatus according to claim 10 wherein the haulage carriage is movable by an internal combustion drive unit. 

1. A method for vertical mining of underground cavities wherein said mining is carried out with a drill unit which is movably suspended on rail means fastened to the roof of said underground cavity and extending along said roof into a raise, whereby said drill unit can be removed from the mining area during blasting operations and loosened material can be removed without hindrance during the drilling operations, the mining operations being started at that end of the underground cavity located remotest from the raise connected thereto and being carried out stepwise towards and up to said raise; a first roof area is drilled, the rail means fastened to the roof of the underground cavity are removed only from that portion of roof area which has been drilled, and the drilled roof area is then blasted away; thereafter a new roof area located nearer said raise is drilled, the rail means fastened to the new drilled roof area is removed, and the blasting thereof is carried out; this procedure is repeated until said raise is reached; and rail means are then fastened in the new roof formed and the process repeated until the height of the underground cavity equals that of the raise.
 2. A method for mining in barren rocks or ore bodies comprising the step of driving a haulage drift, driving a raise upwards from said haulage drift, driving a parallel drift parallel with and above said haulage drift, and driving tapping holes for loosened material between said parallel drift and said haulage drift, whereafter rail means are secured to the roof of the parallel drift and mining equipment which includes a drill unit is movably suspended from said rail means, horizontal breaking is started from said mining equipment and continues stepwise by the installation of new rail means as the work progresses, the mining equipment being brought into safety between each blasting via said raise, whereupon, when the horizontal mining is finished, and a horizontally widened cavity is thereby obtained, vertical mining is started and carried out from said suspended equipment over the full area of the roof of said cavity to remove a layer of a certain thickness from said area, the mining equipment including the rail means is then withdrawn to the raise and the rail means are fastened in the new roof formed, and the vertical mining process is repeated for a next layer of the roof, the vertical mining being repeated a number of times determined by the height of said raise and the thickness of said layers.
 3. A method according to claim 2 wherein, during the successive vertical mining, when a new set of rail means have been installed on the roof of the cavity, mining is started each time at a location as remote as possible from the raise and is carried out stepwise by drilling a first roof area, removing the rail means fastened to said first area, blasting said first area, thereafter drilling a new roof area located nearer said raise, removing the rail means fastened to said new area, blasting said new area, and so on until said raise is reached.
 4. A meThod according to claim 3 wherein said stepwise mining is carried out in a fan-shaped pattern.
 5. A method according to claim 2 wherein, during or after the forming of said raise, rail means are fastened in the wall of the raise, whereupon said rail means on the successive roofs of the parallel drift and said cavity are connected to said rail means on the wall of the raise in order to facilitate withdrawal of the mining equipment.
 6. A method according to claim 5 wherein a service drift is arranged to end in the raise at a place remote from the cavity and further rail means are installed in the roof of said service drift and connected to the rail means of the raise whereby, during mining, blasting is remotely controlled from said service drift.
 7. A method for driving, in barren rocks or ore bodies, substantially horizontal drifts or upwardly inclined drifts having an inclination less than the angle of repose of the loosened material, comprising the steps of removably securing rail means to the roof of said drift, movably suspending from said rail means a mining equipment which includes a drill unit, drilling and loading blast holes from said suspended mining equipment, moving the mining equipment to a safe position via the rail means, blasting, bringing the mining equipment forward again via the rail mean to the working area independently of the extent to which loosened material has been spread away from the blasting area along the drift, and repeating the drilling and loading steps while simultaneously removing the loosened material.
 8. The method of claim 7 including the step of movably suspending a material removal device from said rail means, said step of removing the loosened material being effected with the aid of the suspended material removal device.
 9. A method according to claim 8 wherein the loading of said removal device is started in the center of the loosened material.
 10. Apparatus for driving substantially horizontal drifts or upwardly inclined drifts in barren rocks or ore bodies with said drifts having an inclination less than the angle of repose of the material which is loosened during said driving, comprising rail means removably fastened to the roof of the drift, a mining equipment including a drill unit movably suspended from said roof-mounted rail means, a loading unit, a haulage carriage, and means for movably suspending said loading unit and said haulage carriage from said rail means.
 11. Apparatus according to claim 10, wherein the loading unit comprises a frame, a loading pipe, a scraper, and a scrape loader.
 12. Apparatus according to claim 10, wherein the loading unit is movable upwards along the rail means either by a drill unit or the haulage carriage.
 13. Apparatus according to claim 10, wherein the haulage carriage is movable by a pneumatic drive unit.
 14. Apparatus according to claim 10, wherein the haulage carriage is movable by an electric motor drive unit.
 15. Apparatus according to claim 10 wherein the haulage carriage is movable by an internal combustion drive unit. 